fix(make-pdf): write browse-bound temp files under the safe-dirs allowlist

os.tmpdir() on macOS resolves to /var/folders/..., which fails browse's
safe-dirs validation ([/tmp, cwd]) since the v1.6.0.0 --from-file
tightening. Default PDF output (generate with no -o), the preview HTML,
tmpFile() scratch files, and setup's smoke-test fixture/output all wrote
there, so browse rejected the paths it was asked to read or write.
Export PAYLOAD_TMP_DIR from browseClient (the existing TEMP_DIR
convention: os.tmpdir() on Windows, /tmp elsewhere) and route
orchestrator.ts and setup.ts temp files through it.

Contributed by @lvthewah (PR #2505; the browse-binary directory guard
from that PR landed separately via PR #2538).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

make-pdf/src/browseClient.ts

@@ -195,16 +195,18 @@ function runBrowse(args: string[]): string {
 }
 
 /**
- * Write a payload to a tmp file and return the path. Used for any payload
+ * Temp dir for any file handed to browse (payloads, rendered HTML, PDF output).
- * >4KB to avoid Windows argv limits (Codex round 2 #3).
  *
  * Path must be under the browse safe-dirs allowlist (/tmp or cwd on
  * non-Windows; os.tmpdir on Windows).  v1.6.0.0 tightened --from-file
  * validation to close a CLI/API parity gap (PR #1103), so os.tmpdir()
  * on macOS (/var/folders/...) now fails validateReadPath.  Use the same
  * TEMP_DIR convention as browse/src/platform.ts.
+ *
+ * Exported because orchestrator.ts and setup.ts write files that browse must
+ * read back; os.tmpdir() there trips the same validateReadPath rejection.
  */
-const PAYLOAD_TMP_DIR = process.platform === "win32" ? os.tmpdir() : "/tmp";
+export const PAYLOAD_TMP_DIR = process.platform === "win32" ? os.tmpdir() : "/tmp";
 
 function writePayloadFile(payload: Record<string, unknown>): string {
   const hash = crypto.createHash("sha256")

make-pdf/src/orchestrator.ts

@@ -15,7 +15,6 @@
  */
 
 import * as fs from "node:fs";
-import * as os from "node:os";
 import * as path from "node:path";
 import * as crypto from "node:crypto";
 import { spawn } from "node:child_process";
@@ -86,7 +85,7 @@ export async function generate(opts: GenerateOptions): Promise<string> {
 
   const to = opts.to ?? "pdf";
   const outputPath = path.resolve(
-    opts.output ?? path.join(os.tmpdir(), `${deriveSlug(input)}.${to}`),
+    opts.output ?? path.join(browseClient.PAYLOAD_TMP_DIR, `${deriveSlug(input)}.${to}`),
   );
 
   // Stage 1: read markdown
@@ -358,7 +357,7 @@ export async function preview(opts: PreviewOptions): Promise<string> {
   progress.end("Rendering HTML", `${rendered.meta.wordCount} words`);
 
   // Write to a stable path under /tmp so the user can reload in the same tab.
-  const previewPath = path.join(os.tmpdir(), `make-pdf-preview-${deriveSlug(input)}.html`);
+  const previewPath = path.join(browseClient.PAYLOAD_TMP_DIR, `make-pdf-preview-${deriveSlug(input)}.html`);
   fs.writeFileSync(previewPath, rendered.html, "utf8");
 
   progress.begin("Opening preview");
@@ -378,7 +377,7 @@ function deriveSlug(p: string): string {
 
 function tmpFile(ext: string): string {
   const hash = crypto.randomBytes(6).toString("hex");
-  return path.join(os.tmpdir(), `make-pdf-${process.pid}-${hash}.${ext}`);
+  return path.join(browseClient.PAYLOAD_TMP_DIR, `make-pdf-${process.pid}-${hash}.${ext}`);
 }
 
 function tryOpen(pathOrUrl: string): void {

make-pdf/src/setup.ts

@@ -10,7 +10,6 @@
  *   6. Print a 3-command cheatsheet
  */
 
-import * as os from "node:os";
 import * as path from "node:path";
 import * as fs from "node:fs";
 
@@ -77,8 +76,8 @@ export async function runSetup(): Promise<void> {
     "The second paragraph contains curly quotes (\"hello\"), an em dash -- like this, and an ellipsis... all of which should render correctly.",
     "",
   ].join("\n");
-  const fixturePath = path.join(os.tmpdir(), `make-pdf-smoke-${process.pid}.md`);
+  const fixturePath = path.join(browseClient.PAYLOAD_TMP_DIR, `make-pdf-smoke-${process.pid}.md`);
-  const outPath = path.join(os.tmpdir(), `make-pdf-smoke-${process.pid}.pdf`);
+  const outPath = path.join(browseClient.PAYLOAD_TMP_DIR, `make-pdf-smoke-${process.pid}.pdf`);
   fs.writeFileSync(fixturePath, fixture, "utf8");
 
   try {